Can it be done and is it even the best way to go. I want to swap a rebuilt 4.0l into an older 89yj. I am guessing I will need the computer and fuel delivery system, but is this moderately easy? Oh one other thing anyone know how much punch a 4.2 with injection on it puts out? Ultimately I have no idea what I am going to do yet just want some sage advise and maybe a few horror stories.hehehe. Thanksfor any help